Recently, the Institute of Agricultural Resources and Regional Planning (IARRP), at the Chinese Academy of Agricultural Sciences (CAAS), hosted a project progress meeting and on-site observation exchanges for the key national R&D project under the 14th Five-Year Plan (2021-2025). The meeting was entitled "Formation Mechanisms and Key Ecological Regulation Technologies for Complex Constraints in Red and Yellow Soil Farmland in Southern China" and it was held in Guiyang, capital of China’s Southwest Guizhou province. The event was attended by preeminent experts such as Academician Xu Minggang from the Chinese Academy of Engineering. Also participating were leaders from the Development Center of Science and Technology, MARA, the Department of Major R&D Programs of CAAS, the Guizhou Academy of Agricultural Sciences, and the Soil and Fertilizer Work Station of the Guizhou Provincial Department of Agriculture and Rural Affairs. Joining them were over 60 project team members from more than 10 research institutions across the country. 

Project lead researcher Zhang Huimin highlighted the fact that the project has pioneered a novel method for the comprehensive diagnosis of complex soil constraints — including soil acidity, stickiness, compaction, and infertility — in red and yellow soil regions. It has identified the major types of soil complex soil constraints and the interconnections between constraints across different land use types — including drylands, paddy fields, and rice-upland rotations in these areas. The project has also elucidated the technical principles for the synergistic mitigation of these complex soil constraints, registered specialized fertilizers for crops — such as rice, peanuts, and sweet potatoes — and developed equipment for organic-inorganic compound granulation and cyclone-type organic fertilizer applicators for sloped farmland. Demonstration zones of 1,000 mu (66.7 hectares) each have been established in Fuquan, Guizhou province; Jinxian, Jiangxi province; and Binyang, Guangxi Zhuang autonomous region. By implementing techniques — such as acid reduction, soil fertility enhancement, and ecological regulation — the project has effectively mitigated the issues of soil acidification, compaction, and nutrient imbalances. 

During the meeting, five project leaders presented detailed reports on the formation mechanisms of complex soil constraints in red and yellow soils, the mechanisms underlying their adverse effects, the development of new products for synergistic mitigation, the development of key technologies, and the demonstration of integrated technical approaches.

Participants also visited the 1,159 mu demonstration zone in Lu'ao village, Luping town, in Fuquan city. This area faces significant challenges with strong soil acidity, heavy textures, and fertility degradation. In response to these regional soil conditions, the demonstration zone has integrated core technologies for soil acidity amelioration, improvement, and soil structural improvement through straw incorporation, These technologies have been supported by products such as mineral-based soil amendments, environmentally friendly smart fertilizers, and biochar, together with complementary practices including maize-soybean intercropping, contour ridge cultivation, and winter green manure planting. Through this integrated approach, a locally adapted model has been established for the coordinated alleviation and ecological prevention and control of multiple constraints in yellow-soil dryland.. After nearly two years of demonstration application, the maize yield increased by 9% in 2025, and the rapeseed yield increased by 22% in 2026.

Academician Xu Minggang emphasized that the issue of complex soil constraints have severely hindered agricultural production in China.. The project's initial achievements in addressing the degradation of acidic farmland in southern China was promising. He stressed the importance of continuous efforts in soil improvement to consolidate and expand these achievements — thereby providing a solid foundation for ensuring national food security and sustainable agricultural development.